Shell Programming and Scripting

#! /bin/ksh

..(some lines are here..)

for t in (LIST)
do
a=function($t)

#here I want to wait till the function hangs for 5 secs else want to continue the loop for other values of t.

done


if [ $a = 1 ];then
.............
fi
......
......................

Suppose in this script; inside the for loop the function() hangs and unable return the result; then I want to wait till 5 secs. If the function hangs more than 5 secs for a certein variable then I want to continue the loop for the other variables in the LIST .

plz help...

You run your function in the background. After that starts, you sleep 5 seconds, then kill it with %1. Then call wait.

Code:

date
function($t) &

# get job number
x=`jobs -p`
# kill that job in 5 seconds
{ sleep 5; kill $x; } &>/dev/null &

# wait for something to finish
wait $x
date

The wait will complete when all sub-processes have finished. The kill will silently fail if the job completes first.

Hope this helps.

=======================
Thanks a lot...
I tried this as follows.. But it is not working..
-------------------------------------------------
#scipt name: fun
f()
{
enccp -c mas start service_name -v -myPwd password
# This is a IBM-encina command that is creating the sevice.. Which is hanging in this case
}

f &
x=`jobs -p`
{ sleep 1; kill $x; } &>/dev/null &
wait $x
date

OUTPUT:
------------------------------------------------------
[/home2/niroj_p]./fun
Wed Sep 10 11:28:59 IST 2008
[/home2/niroj_p]starting service_name
retrieving attributes of object service_name ... done
setting up the server resources
retrieving node object mars6 ... done
creating file system path /var/opt/encina/local/subsys/encina/css6/server/service_name... exists
retrieving encina server group name ... done
retrieving encina administration organization ... done
.................
...........................Then it is hanging as usual

Can you kill it with a regular kill from the command line? If not, does it respond to other signals? (The default signal is SIGTERM, usually signal 15. Other useful signals to try are 2 = SIGINT and -- in utter desperation only -- 9 = SIGKILL.) Ctrl-C usually sends SIGINT.

I tried this program with using for loop...

=========================================
set -x

f()
{

enccp -c mas start serv_nm -v -myPwd encina_admin

}

i=0
for i in 1 2
do
f &
x=`jobs -p`
{ sleep 1; kill -9 $x; } &>/dev/null &
wait $x
date
i=`expr $i + 1`
done

===========================================

OUTPUT:
-------------

[/home2/niroj_p]./fun
+ i=0
+ + f
+ enccp -c mas start serv_nm -v -myPwd passwd
+ jobs -p
x=0
+ sleep 1
+ 1> /dev/null
+ wait 0
+ date
Wed Sep 10 13:57:24 IST 2008
+ + expr 1 + 1
i=2
+ f
+ + enccp -c mas start serv_nm -v -myPwd passwd
+ + jobs -p
x=0
0
0
+ sleep 1
+ 1> /dev/null
+ wait 0 0 0
+ date
Wed Sep 10 13:57:24 IST 2008
+ + expr 2 + 1
i=3
[/home2/niroj_p]starting serv_nm
retrieving attributes of object serv_nm ... done
setting up the server resources
retrieving node object mars6 ... done
creating file system path /var/opt/encina/local/subsys/encina/css6/server/serv_nm ... exists
retrieving encina server group name ... done
retrieving encina administration organization ... done
starting serv_nm
retrieving attributes of object serv_nm ... done
setting up the server resources
retrieving node object mars6 ... done
creating file system path /var/opt/encina/local/subsys/encina/css6/server/serv_nm... exists
retrieving encina server group name ... done
retrieving encina administration organization ... done
+ kill -9 0 # Kill is working nice

=====================
After this I have to enter any key to come out from the process.
That I want to avoid..


Thank u friends...

Are you sure you really must use kill -9? It can be dangerous. Try with kill -2 first.

The proper (or at least customary, and easiest) way to get the process ID is with x=$! right after starting the background job.

I don't understand the for loop, do you start two separate processes and sleep a maximum of one second between them? I'm not certain about the need to press a key after the process is killed; are you sure it's not the second round of the loop?

Cool! I never knew that one. That's why I come here.